What is the approximate size range for worker bigheaded ants depending on their species?

The size range for worker bigheaded ants is correctly identified as 1.5-4.5 mm depending on their species. Worker bigheaded ants, belonging to the genus Pheidole, are known for their distinctively large heads compared to their bodies, which is a characteristic feature of this group. The measurement in millimeters accurately reflects the typical physical dimensions of these ants. Understanding the size range is crucial for identification and studying their behavior and habitat.

The other options provide size ranges that are either in centimeters or represent ranges that exceed the typical measurements observed for these ants. Since bigheaded ants are relatively small compared to other insects, sizes given in centimeters do not accurately align with their actual dimensions, which is fundamental knowledge for anyone studying or working with this species.